The Clean Air Act (CAA) mandates that EPA regulate emissions of more than 180 commonly used industrial chemicals and compounds known as hazardous air pollutants
(HAPs). Unfortunately, EPA does not regulate or restrict emissions of these HAPs based on the health risks posed by ambient-air concentrations or actual exposures
to these toxic substances. Instead, EPA has primarily regulated emissions of these HAPs by imposing technology-based emission controls on major sources of these HAPs. Years after those controls are installed, EPA evaluates the health risks that remain, i.e., residual risks, from facilities that emit the HAPs. Even then, EPA does not evaluate these health risks based on actual ambient concentrations of these pollutants—instead, EPA bases its assessment on engineering calculations. EPA’s own
research indicates that air pollution is posing significant health risks, particularly in urban areas. EPA needs to focus on devising and implementing the programs that
were delegated to them under the 1990 CAA Amendments to restrict ambient concentrations of HAPs to levels that will provide adequate protection of public health.